Complete response letter (CRL)
The FDA's formal notice that it will not approve a drug application in its current form, listing the deficiencies a resubmission must address.
"The FDA rejected the drug" almost always means a CRL. it is a document with specific contents, and what it asked for is the test every resubmission should be read against.
What it is
When the FDA completes its review and decides against approval, it issues a complete response letter describing what would be needed — new trials, new analyses, manufacturing fixes. The letter itself is typically not published by the FDA at the time (companies characterize it), which is why careful coverage distinguishes what the agency asked for from what the sponsor says it asked for.
The live psychiatric example
MDMA-assisted therapy received a CRL signed 8 August 2024, after an advisory committee voted 9–2 that effectiveness was not established. The letter itself, which FDA has since published, says “the most efficient path to address the clinical issues above would be to conduct a new clinical trial to assess the durability of effect and adequately characterize the safety of midomafetamine.” FDA has published no record of a resubmission. Any future resubmission should be read against that ask; our status page tracks it. (Corrected 29 September 2026: this entry earlier described a 2026 resubmission and the CRL's contents from the sponsor's and an advocacy group's statements, which do not meet our citation rules.)
Somewhere to put it
free. anonymous. people who’ve been where you are 🤍
get veisund — it’s freewant the deeper story? read prescribed to fail
Questions
Is a CRL final?
No — sponsors can resubmit with new evidence, meet with the agency, or appeal. Many approved drugs took a CRL on the way. It is a closed door with instructions on it, not a locked one.
More from the glossary
veisund is not a clinical product and does not diagnose, treat, or cure any condition. if you’re in crisis, call or text 988 (u.s.), 24/7, free.